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Abstract:

The present disclosure provides a method for evaluating cross-cell
coverage, which includes: finding, according to a neighboring cell
configuration table of a cell in a base station, a cell with a number of
configured neighboring cells that is larger than a number threshold for
configured neighboring cells; designating the found cell as an original
cell; carrying out a processing to obtain the cross-cell coverage
evaluation parameters of the original cell; and determining the original
cell i provides and/or suffers from cross-cell coverage when the
cross-cell coverage evaluation parameter of the original cell exceeds
respective cross-cell coverage evaluation thresholds. The present
disclosure further provides an apparatus for evaluating cross-cell
evaluation, which is capable of determining whether or not a cell
provides cross-cell coverage to make parameters of a wireless network
adjusted timely and limit the coverage of the wireless network in a
supposed one.

Claims:

1. A method for evaluating cross-cell coverage, comprising: finding,
according to a neighboring cell configuration table of a cell in a base
station, a cell with a number of configured neighboring cells that is
larger than a number threshold for configured neighboring cells;
designating the found cell as an original cell; processing following
information to get a cross-cell coverage evaluation parameter of the
original cell: local information of a cell from a location information
table of the base station, a mainlobe of the original cell obtained from
a background of the base station, a neighboring cell configuration table
of the original cell, a radius of a smallest concentric circle, and
detailed information during a call process of a mobile terminal; and when
the cross-cell coverage evaluation parameter of the original cell exceeds
a cross-cell coverage evaluation threshold, determining that the original
cell provides and/or suffers from cross-cell coverage.

2. The method according to claim 1, wherein when the cross-cell coverage
evaluation parameter of the original cell exceeds a cross-cell coverage
evaluation threshold, determining that the original cell provides
cross-cell coverage comprises: determining whether a loop on which a
farthest neighboring cell is located is larger than a loop location
threshold for the farthest neighboring cell; when determining that the
loop on which the farthest neighboring cell is located is larger than the
loop location threshold for the farthest neighboring cell, determining
whether a number of loops, on which configured neighboring cells within
the mainlobe of the original cell in the loop, on which the farthest
neighboring cell is located, are located, is larger than a loop number
threshold for the configured neighboring cells within the mainlobe of the
original cell in the loop on which the farthest neighboring cell is
located; when determining the number of loops, on which configured
neighboring cells within the mainlobe of the original cell in the loop,
on which the farthest neighboring cell is located, are located, is larger
than the loop number threshold for the configured neighboring cells
within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located, comparing distances of the mobile
terminal to the original cell and to a neighboring cell with a first
distance threshold and a second distance threshold; when the distance of
the mobile terminal to the original cell is larger than the second
distance threshold, and the distance of the mobile terminal to the
neighboring cell is either smaller than the first distance threshold, or
larger than the first distance threshold and smaller than the second
distance threshold, determining whether a number of handovers of the
mobile terminal between the original cell and the neighboring cell
exceeds a number threshold for handovers of the mobile terminal between
the original cell and the neighboring cell; and when determining that the
number of handovers of the mobile terminal between the original cell and
the neighboring cell exceeds the number threshold for handovers of the
mobile terminal between the original cell and the neighboring cell,
determining that the original cell provides cross-cell coverage.

3. The method according to claim 2, further comprising: when determining
the number of loops, on which configured neighboring cells within the
mainlobe of the original cell in the loop, on which the farthest
neighboring cell is located, are located, is larger than the loop number
threshold for the configured neighboring cells within the mainlobe of the
original cell in the loop on which the farthest neighboring cell is
located, comparing distances of the mobile terminal to the original cell
and to the neighboring cell with the first distance threshold and the
second distance threshold; when the distance of the mobile terminal to
the neighboring cell is larger than the second distance threshold, and
the distance of the mobile terminal to the original cell is either
smaller than the first distance threshold, or larger than the first
distance threshold and smaller than the second distance threshold,
determining whether the number of handovers of the mobile terminal
between the original cell and the neighboring cell exceeds the number
threshold for handovers of the mobile terminal between the original cell
and the neighboring cell; and when determining that the number of
handovers of the mobile terminal between the original cell and the
neighboring cell exceeds the number threshold for handovers of the mobile
terminal between the original cell and the neighboring cell, determining
that the original cell suffers from cross-cell coverage.

4. The method according to claim 1, wherein when the cross-cell coverage
evaluation parameter of the original cell exceeds a cross-cell coverage
evaluation threshold, determining that the original cell suffers from
cross-cell coverage comprises: determining whether a loop on which a
farthest neighboring cell is located is larger than a loop location
threshold for the farthest neighboring cell; when determining that the
loop on which the farthest neighboring cell is located is larger than the
loop location threshold for the farthest neighboring cell, determining
whether a number of loops, on which configured neighboring cells within
the mainlobe of the original cell in the loop, on which the farthest
neighboring cell is located, are located, is larger than a loop number
threshold for the configured neighboring cells within the mainlobe of the
original cell in the loop on which the farthest neighboring cell is
located; when determining the number of loops, on which configured
neighboring cells within the mainlobe of the original cell in the loop,
on which the farthest neighboring cell is located, are located, is larger
than the loop number threshold for the configured neighboring cells
within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located, comparing distances of the mobile
terminal to the original cell and to a neighboring cell with a first
distance threshold and a second distance threshold; when the distance of
the mobile terminal to the neighboring cell is larger than the second
distance threshold, and the distance of the mobile terminal to the
original cell is either smaller than the first distance threshold, or
larger than the first distance threshold and smaller than the second
distance threshold, determining whether a number of handovers of the
mobile terminal between the original cell and the neighboring cell
exceeds a number threshold for handovers of the mobile terminal between
the original cell and the neighboring cell; and when determining that the
number of handovers of the mobile terminal between the original cell and
the neighboring cell exceeds the number threshold for handovers of the
mobile terminal between the original cell and the neighboring cell,
determining that the original cell suffers from cross-cell coverage.

5. The method according to claim 2, further comprising: inputting a
cross-cell coverage evaluation threshold, before performance of the
processing to get the cross-cell coverage evaluation parameter of the
original cell; the cross-cell coverage evaluation threshold comprises:
the loop location threshold for the farthest neighboring cell, the loop
number threshold for the configured neighboring cells within the mainlobe
of the original cell in the loop on which the farthest neighboring cell
is located, the distance thresholds, and the number threshold for
handovers of the mobile terminal between the original cell and the
neighboring cell when the distances of the mobile terminal to the
original cell and to the neighboring cell are larger than the distance
thresholds.

6. An apparatus for evaluating cross-cell coverage, comprising: an
comparison and determination unit, configured to find, according to a
neighboring cell configuration table of a cell in a base station, a cell
with a number of configured neighboring cells that is larger than a
number threshold for configured neighboring cells, designate the found
cell as an original cell, and determine that the original cell provides
and/or suffers from cross-cell coverage when a cross-cell coverage
evaluation parameter of the original cell exceeds a cross-cell coverage
evaluation threshold; and a processing unit, configured to process
following information to get the cross-cell coverage evaluation
parameter: local information of a cell from a location information table
of the base station, a mainlobe of the original cell obtained from a
background of the base station, a neighboring cell configuration table of
the original cell, a radius of a smallest concentric circle, and detailed
information during a call process of a mobile terminal.

7. The apparatus according to claim 6, wherein the comparison and
determination unit is specifically configured to: determine whether a
loop on which a farthest neighboring cell is located is larger than a
loop location threshold for the farthest neighboring cell; when
determining that the loop on which the farthest neighboring cell is
located is larger than the loop location threshold for the farthest
neighboring cell, determine whether a number of loops, on which
configured neighboring cells within the mainlobe of the original cell in
the loop, on which the farthest neighboring cell is located, are located,
is larger than a loop number threshold for the configured neighboring
cells within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located; when determining the number of
loops, on which configured neighboring cells within the mainlobe of the
original cell in the loop, on which the farthest neighboring cell is
located, are located, is larger than the loop number threshold for the
configured neighboring cells within the mainlobe of the original cell in
the loop on which the farthest neighboring cell is located, compare
distances of the mobile terminal to the original cell and to a
neighboring cell with a first distance threshold and a second distance
threshold; when the distance of the mobile terminal to the original cell
is larger than the second distance threshold, and the distance of the
mobile terminal to the neighboring cell is either smaller than the first
distance threshold, or larger than the first distance threshold and
smaller than the second distance threshold, determine whether a number of
handovers of the mobile terminal between the original cell and the
neighboring cell exceeds a number threshold for handovers of the mobile
terminal between the original cell and the neighboring cell; and when
determining that the number of handovers of the mobile terminal between
the original cell and the neighboring cell exceeds the number threshold
for handovers of the mobile terminal between the original cell and the
neighboring cell, determine that the original cell provides cross-cell
coverage.

8. The apparatus according to claim 6, wherein the comparison and
determination unit, when determining the number of loops, on which
configured neighboring cells within the mainlobe of the original cell in
the loop, on which the farthest neighboring cell is located, are located,
is larger than the loop number threshold for the configured neighboring
cells within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located, is further configured to: compare
distances of the mobile terminal to the original cell and to the
neighboring cell with the first distance threshold and the second
distance threshold; when the distance of the mobile terminal to the
neighboring cell is larger than the second distance threshold, and the
distance of the mobile terminal to the original cell is either smaller
than the first distance threshold, or larger than the first distance
threshold and smaller than the second distance threshold, determine
whether the number of handovers of the mobile terminal between the
original cell and the neighboring cell exceeds the number threshold for
handovers of the mobile terminal between the original cell and the
neighboring cell; and when determining that the number of handovers of
the mobile terminal between the original cell and the neighboring cell
exceeds the number threshold for handovers of the mobile terminal between
the original cell and the neighboring cell, determine that the original
cell suffers from cross-cell coverage.

9. The apparatus according to claim 6, wherein the comparison and
determination unit is specifically configured to: determine whether a
loop on which a farthest neighboring cell is located is larger than a
loop location threshold for the farthest neighboring cell; when
determining that the loop on which the farthest neighboring cell is
located is larger than the loop location threshold for the farthest
neighboring cell, determine whether a number of loops, on which
configured neighboring cells within the mainlobe of the original cell in
the loop, on which the farthest neighboring cell is located, are located,
is larger than a loop number threshold for the configured neighboring
cells within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located; when determining the number of
loops, on which configured neighboring cells within the mainlobe of the
original cell in the loop, on which the farthest neighboring cell is
located, are located, is larger than the loop number threshold for the
configured neighboring cells within the mainlobe of the original cell in
the loop on which the farthest neighboring cell is located, compare
distances of the mobile terminal to the original cell and to a
neighboring cell with a first distance threshold and a second distance
threshold; when the distance of the mobile terminal to the neighboring
cell is larger than the second distance threshold, and the distance of
the mobile terminal to the original cell is either smaller than the first
distance threshold, or larger than the first distance threshold and
smaller than the second distance threshold, determine whether a number of
handovers of the mobile terminal between the original cell and the
neighboring cell exceeds a number threshold for handovers of the mobile
terminal between the original cell and the neighboring cell; and when
determining that the number of handovers of the mobile terminal between
the original cell and the neighboring cell exceeds the number threshold
for handovers of the mobile terminal between the original cell and the
neighboring cell, determine that the original cell suffers from
cross-cell coverage.

10. The apparatus according to claim 6, further comprising an input unit,
configured to input the cross-cell evaluation threshold to the comparison
and determination unit; wherein the cross-cell coverage evaluation
threshold comprises: the loop location threshold for the farthest
neighboring cell, the loop number threshold for the configured
neighboring cells within the mainlobe of the original cell in the loop on
which the farthest neighboring cell is located, the distance thresholds,
and the number threshold for handovers of the mobile terminal between the
original cell and the neighboring cell when the distances of the mobile
terminal to the original cell and to the neighboring cell are larger than
the distance thresholds.

11. The method according to claim 3, further comprising: inputting a
cross-cell coverage evaluation threshold, before performance of the
processing to get the cross-cell coverage evaluation parameter of the
original cell; the cross-cell coverage evaluation threshold comprises:
the loop location threshold for the farthest neighboring cell, the loop
number threshold for the configured neighboring cells within the mainlobe
of the original cell in the loop on which the farthest neighboring cell
is located, the distance thresholds, and the number threshold for
handovers of the mobile terminal between the original cell and the
neighboring cell when the distances of the mobile terminal to the
original cell and to the neighboring cell are larger than the distance
thresholds.

12. The method according to claim 4, further comprising: inputting a
cross-cell coverage evaluation threshold, before performance of the
processing to get the cross-cell coverage evaluation parameter of the
original cell; the cross-cell coverage evaluation threshold comprises:
the loop location threshold for the farthest neighboring cell, the loop
number threshold for the configured neighboring cells within the mainlobe
of the original cell in the loop on which the farthest neighboring cell
is located, the distance thresholds, and the number threshold for
handovers of the mobile terminal between the original cell and the
neighboring cell when the distances of the mobile terminal to the
original cell and to the neighboring cell are larger than the distance
thresholds.

13. The apparatus according to claim 7, further comprising an input unit,
configured to input the cross-cell evaluation threshold to the comparison
and determination unit; wherein the cross-cell coverage evaluation
threshold comprises: the loop location threshold for the farthest
neighboring cell, the loop number threshold for the configured
neighboring cells within the mainlobe of the original cell in the loop on
which the farthest neighboring cell is located, the distance thresholds,
and the number threshold for handovers of the mobile terminal between the
original cell and the neighboring cell when the distances of the mobile
terminal to the original cell and to the neighboring cell are larger than
the distance thresholds.

14. The apparatus according to claim 8, further comprising an input unit,
configured to input the cross-cell evaluation threshold to the comparison
and determination unit; wherein the cross-cell coverage evaluation
threshold comprises: the loop location threshold for the farthest
neighboring cell, the loop number threshold for the configured
neighboring cells within the mainlobe of the original cell in the loop on
which the farthest neighboring cell is located, the distance thresholds,
and the number threshold for handovers of the mobile terminal between the
original cell and the neighboring cell when the distances of the mobile
terminal to the original cell and to the neighboring cell are larger than
the distance thresholds.

15. The apparatus according to claim 9, further comprising an input unit,
configured to input the cross-cell evaluation threshold to the comparison
and determination unit; wherein the cross-cell coverage evaluation
threshold comprises: the loop location threshold for the farthest
neighboring cell, the loop number threshold for the configured
neighboring cells within the mainlobe of the original cell in the loop on
which the farthest neighboring cell is located, the distance thresholds,
and the number threshold for handovers of the mobile terminal between the
original cell and the neighboring cell when the distances of the mobile
terminal to the original cell and to the neighboring cell are larger than
the distance thresholds.

Description:

TECHNICAL FIELD

[0001] The present disclosure relates to the field of wireless network
optimization and in particular to a method and an apparatus for
evaluating cross-cell coverage in the wireless network optimization.

BACKGROUND

[0002] In a narrow sense, wireless network optimization refers to finding
a cause of degradation of network quality through a parameter analysis
and a hardware check of an currently operating network, performing a
parameter modification, a network structure adjustment and a device
configuration adjustment, etc., thereby greatly benefiting from the
existing network resources, guaranteeing high-quality operation of a
system and achieving a highest profit with a lowest investment.

[0003] In a general sense, wireless network optimization includes various
aspects ranging from determination of network size, network capacity and
capacity expansion scheme, to site location selection and network
construction, and further to network parameter configuration. Each step
performed during the wireless network optimization may be associated with
network quality and affect development of the network. Typically, a
network optimization can be divided into the following three stages:

[0004] (1) determining the capacity of the wireless network and the
requirements on the capacity expansion of the wireless network;

[0005] (2) selecting a location for a site and constructing the site
according to the geographic features of the region in which the wireless
network is located;

[0006] (3) configuring parameters for the wireless network.

[0007] The stages (1) and (2) constitute a wireless network planning stage
mainly for planning the specific distribution of network architecture,
and the stage (3) is a wireless network configuration stage for
implementing a wireless coverage. Each of the three stages is highly
important. In the case that requirements on engineering quality are met
in the stages (1) and (2), the stage (3) becomes particularly important.

[0008] During the process of existing wireless network optimization, from
someone's viewpoint, the further a base station covers, the larger the
signal-receiving area is. Therefore, in order to meet the requirements on
wireless coverage, parameters such as antenna height and transmission
power of base station, generally intend to be larger than normal, which
though meets the coverage requirements, brings an immeasurable negative
effect.

[0009] Taking a Code Division Multiple Access (CDMA) network as an
example, the coverage distance of a base station is determined by such
factors as the location of the base station and the density of sites. The
coverage distance should be proper, neither too long nor too short.
However, in order to meet the requirements on wireless coverage, a base
station covers a distance actually much further than it is supposed to,
and thus a mobile terminal far away from the base station can receive
from the base station a signal with strength higher than a strength
threshold of the mobile terminal signals. At this time, the mobile
terminal sends a pilot measurement report, in which the phase of the cell
with respect to the newly detected base station is carried, to its
serving base station. Then, according to the phase of the cell with
respect to the newly detected base station sent by the mobile station,
the serving base station calculates a pseudo random code (PN) of the cell
in which the new base station is located by dividing the phase by 64,
wherein PN indicates an identifier of a cell in CDMA network, and a cell
is associated with a PN. Then, the base station conducts a search in the
neighboring cell configuration table to find a neighboring cell
corresponding to the calculated PN, and establishes new channel resource
for the mobile terminal in the neighboring cell. The neighboring cell
configuration table is created based on distances between cells and the
direction angles of cells. Specifically, the distances between cells
should be as short as possible, and neighboring cells are preferred.
Also, the direction angles of cells should be opposite to each other,
that is, cells should have as many overlapping coverage areas as
possible, so that a mobile terminal moving in a cell can receive a signal
from another cell easily. Generally, a base station may enable a mobile
terminal to handover to a new cell by sending cell handover indication
information to the mobile terminal. However, if the newly detected cell
is a cross-cell-coverage cell (i.e., a cell which has a larger coverage
area than it is supposed to), and the active set cell which is serving
the mobile terminal does not configure the newly detected cell, but
configures another cell which has a same PN as that of the newly detected
cell as a neighboring cell, the mobile terminal may detect a signal from
the base station in newly detected cell, however, the serving base
station will determine the target cell for handover add as the another
cell having the same PN, leading to an error handover add and thus a call
drop of the mobile terminal which severely affects user experience. The
term "handover add" means, a serving base station establishes two-channel
resources for a mobile terminal moving to the boundary of its serving
cell, which are the channel resources of the serving cell and the channel
resources of the cell to be hand over, respectively.

[0010] FIG. 1 shows an example of the cross-cell coverage of a cell, it
can be seen from FIG. 1 that a mobile terminal initiates a call through a
Base Transceiver Station (BTS) 4 and detects, during the communication, a
signal from a cell of a BTS1, which provides cross-cell coverage and thus
is not configured as a neighboring cell by the BTS4. After detecting the
signal from the cell of the BTS1, the mobile terminal sends a pilot
measurement report to the BTS4. The BTS4 finds, through calculation, that
the PN of the cell of the BTS1 is PN2, and then conducts a search in the
neighboring cell configuration table of the cell to find that the PN of
the cell of a BTS3 is also PN2. Accordingly, the BTS4 incorrectly
establishes new channel resources for the mobile terminal in the cell of
the BTS3, while the signal actually detected by the mobile terminal is
one from the cell of the BTS1. As a result, an error handover performed
by the BTS4 causes a call drop of the mobile terminal.

[0011] In view of the above, it remains a problem needing an urgent
solution how to effectively avoid the cross-cell coverage of a cell.

SUMMARY

[0012] Therefore, the main objective of the present disclosure is to
provide a method and an apparatus for evaluating cross-cell coverage in
wireless network optimization which are capable of effectively finding a
cell having cross-cell coverage in a wireless network.

[0013] In order to achieve the objective above, the technical solution of
the present disclosure is realized as follows.

[0014] A method for evaluating cross-cell coverage is provided in the
present disclosure, which includes:

[0015] finding, according to a neighboring cell configuration table of a
cell in a base station, a cell with a number of configured neighboring
cells that is larger than a number threshold for configured neighboring
cells;

[0016] designating the found cell as an original cell;

[0017] processing following information to get a cross-cell coverage
evaluation parameter of the original cell: [0018] local information of
a cell from a location information table of the base station, a mainlobe
of the original cell obtained from a background of the base station, a
neighboring cell configuration table of the original cell, a radius of a
smallest concentric circle, and detailed information during a call
process of a mobile terminal; and

[0019] when the cross-cell coverage evaluation parameter of the original
cell exceeds a cross-cell coverage evaluation threshold, determining that
the original cell provides and/or suffers from cross-cell coverage.

[0020] In the aforementioned solution, when the cross-cell coverage
evaluation parameter of the original cell exceeds a cross-cell coverage
evaluation threshold, determining that the original cell provides
cross-cell coverage may include:

[0021] determining whether a loop on which a farthest neighboring cell is
located is larger than a loop location threshold for the farthest
neighboring cell;

[0022] when determining that the loop on which the farthest neighboring
cell is located is larger than the loop location threshold for the
farthest neighboring cell, determining whether a number of loops, on
which configured neighboring cells within the mainlobe of the original
cell in the loop, on which the farthest neighboring cell is located, are
located, is larger than a loop number threshold for the configured
neighboring cells within the mainlobe of the original cell in the loop on
which the farthest neighboring cell is located;

[0023] when determining the number of loops, on which configured
neighboring cells within the mainlobe of the original cell in the loop,
on which the farthest neighboring cell is located, are located, is larger
than the loop number threshold for the configured neighboring cells
within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located, comparing distances of the mobile
terminal to the original cell and to a neighboring cell with a first
distance threshold and a second distance threshold;

[0024] when the distance of the mobile terminal to the original cell is
larger than the second distance threshold, and the distance of the mobile
terminal to the neighboring cell is either smaller than the first
distance threshold, or larger than the first distance threshold and
smaller than the second distance threshold, determining whether a number
of handovers of the mobile terminal between the original cell and the
neighboring cell exceeds a number threshold for handovers of the mobile
terminal between the original cell and the neighboring cell; and

[0025] when determining that the number of handovers of the mobile
terminal between the original cell and the neighboring cell exceeds the
number threshold for handovers of the mobile terminal between the
original cell and the neighboring cell, determining that the original
cell provides cross-cell coverage.

[0026] In the aforementioned solution, the method may further include:

[0027] when determining the number of loops, on which configured
neighboring cells within the mainlobe of the original cell in the loop,
on which the farthest neighboring cell is located, are located, is larger
than the loop number threshold for the configured neighboring cells
within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located,

[0028] comparing distances of the mobile terminal to the original cell and
to the neighboring cell with the first distance threshold and the second
distance threshold;

[0029] when the distance of the mobile terminal to the neighboring cell is
larger than the second distance threshold, and the distance of the mobile
terminal to the original cell is either smaller than the first distance
threshold, or larger than the first distance threshold and smaller than
the second distance threshold, determining whether the number of
handovers of the mobile terminal between the original cell and the
neighboring cell exceeds the number threshold for handovers of the mobile
terminal between the original cell and the neighboring cell; and

[0030] when determining that the number of handovers of the mobile
terminal between the original cell and the neighboring cell exceeds the
number threshold for handovers of the mobile terminal between the
original cell and the neighboring cell, determining that the original
cell suffers from cross-cell coverage.

[0031] In the aforementioned solution, the method may further include:

[0032] inputting a cross-cell coverage evaluation threshold, before
performance of the processing to get the cross-cell coverage evaluation
parameter of the original cell;

[0033] the cross-cell coverage evaluation threshold comprises: the loop
location threshold for the farthest neighboring cell, the loop number
threshold for the configured neighboring cells within the mainlobe of the
original cell in the loop on which the farthest neighboring cell is
located, the distance thresholds, and the number threshold for handovers
of the mobile terminal between the original cell and the neighboring cell
when the distances of the mobile terminal to the original cell and to the
neighboring cell are larger than the distance thresholds.

[0034] An apparatus for evaluating cross-cell coverage is also provided in
the present disclosure, which includes:

[0035] an comparison and determination unit, configured to [0036] find,
according to a neighboring cell configuration table of a cell in a base
station, a cell with a number of configured neighboring cells that is
larger than a number threshold for configured neighboring cells, [0037]
designate the found cell as an original cell, and [0038] determine that
the original cell provides and/or suffers from cross-cell coverage when a
cross-cell coverage evaluation parameter of the original cell exceeds a
cross-cell coverage evaluation threshold; and

[0039] a processing unit, configured to process following information to
get the cross-cell coverage evaluation parameter: [0040] local
information of a cell from a location information table of the base
station, a mainlobe of the original cell obtained from a background of
the base station, a neighboring cell configuration table of the original
cell, a radius of a smallest concentric circle, and detailed information
during a call process of a mobile terminal.

[0041] In the aforementioned solution, the comparison and determination
unit may be specifically configured to: determine whether a loop on which
a farthest neighboring cell is located is larger than a loop location
threshold for the farthest neighboring cell;

[0042] when determining that the loop on which the farthest neighboring
cell is located is larger than the loop location threshold for the
farthest neighboring cell, determine whether a number of loops, on which
configured neighboring cells within the mainlobe of the original cell in
the loop, on which the farthest neighboring cell is located, are located,
is larger than a loop number threshold for the configured neighboring
cells within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located;

[0043] when determining the number of loops, on which configured
neighboring cells within the mainlobe of the original cell in the loop,
on which the farthest neighboring cell is located, are located, is larger
than the loop number threshold for the configured neighboring cells
within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located, compare distances of the mobile
terminal to the original cell and to a neighboring cell with a first
distance threshold and a second distance threshold;

[0044] when the distance of the mobile terminal to the neighboring cell is
larger than the second distance threshold, and the distance of the mobile
terminal to the original cell is either smaller than the first distance
threshold, or larger than the first distance threshold and smaller than
the second distance threshold, determine whether a number of handovers of
the mobile terminal between the original cell and the neighboring cell
exceeds a number threshold for handovers of the mobile terminal between
the original cell and the neighboring cell; and

[0045] when determining that the number of handovers of the mobile
terminal between the original cell and the neighboring cell exceeds the
number threshold for handovers of the mobile terminal between the
original cell and the neighboring cell, determine that the original cell
suffers from cross-cell coverage.

[0046] It can thus be seen that by using the solutions provided in the
present disclosure, a cell having cross-cell coverage can be effectively
found from wireless network, and the configuration parameters of the cell
can be timely adjusted to limit the coverage of the cell within a desired
range. Accordingly, the problem of call drop caused by cross-cell
coverage may be resolved and user experience may be greatly improved.

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] FIG. 1 is a schematic diagram illustrating the cross-cell coverage
of a cell in a CDMA network;

[0048] FIG. 2 is a flow chart illustrating a method for evaluating
cross-cell coverage according to the present disclosure;

[0049] FIG. 3 is a schematic diagram illustrating distance thresholds R1
and R2 according to the present disclosure;

[0050] FIG. 4 is an exemplary diagram illustrating a cross-cell coverage
evaluation according to the present disclosure;

[0051]FIG. 5 is a schematic diagram illustrating an apparatus for
evaluating cross-cell coverage according to the present disclosure.

DETAILED DESCRIPTION

[0052] A rational parameter configuration can effectively avoid the
cross-cell coverage of a cell, and how to configure parameters more
rationally depends on an effectively and scientifically developed
optimization tool rather than artificial determination and analysis.

[0053] The basic idea of the present disclosure lies in that: according to
the neighboring cell configuration table of a cell in a base station, a
cell with the number of configured neighboring cells that is larger than
a number threshold for configured neighboring cells, which is prone to
have cross-cell coverage, is found and taken as an original cell. A
processing is carried out to obtain a cross-cell coverage evaluation
parameter of the original cell, and it is determined that the original
cell provides or suffers from cross-cell coverage when the cross-cell
coverage evaluation parameter of the original cell exceeds the cross-cell
coverage evaluation threshold, thereby facilitating the following
adjustment on the configuration parameters of the original cell to adjust
the coverage of a wireless network to limit the coverage of a wireless
cell in a supposed one.

[0054] The cross-cell coverage evaluation parameter includes: a loop on
which a farthest neighboring cell is located; the number of loops, on
which configured neighboring cells within the mainlobe of the original
cell in the loop, on which the farthest neighboring cell is located, are
located; the distance between the mobile terminal and the original cell
and the distance between the mobile terminal and a neighboring cell; and
the times of handover of the mobile terminal between the original cell
and the neighboring cell, wherein the mainlobe refers to the included
angle of the antennae of a cell; and correspondingly, the cross-cell
coverage evaluation threshold includes: the loop location threshold for
the farthest neighboring cell, the loop number threshold for the
configured neighboring cells within the mainlobe of the original cell in
the loop on which the farthest neighboring cell is located, the distance
thresholds, and the number threshold for handovers of the mobile terminal
between the original cell and the neighboring cell when the distances of
the mobile terminal to the original cell and to the neighboring cell are
larger than the distance thresholds.

[0055] The evaluation process of the present disclosure is described below
based on a specific embodiment, the apparatus for evaluating cross-cell
coverage provided herein comprises an input unit, a processing unit, a
comparison and determination unit and an output unit; and as shown in
FIG. 2, the method for evaluating cross-cell coverage provided herein
comprises the following steps.

[0056] Step 201: the input unit inputs, to the comparison and
determination unit, a threshold for the number of the neighboring cells
configured, the loop location threshold for the farthest neighboring
cell, the loop number threshold for the configured neighboring cells
within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located, distance thresholds R1 and R2, and
the number threshold for handovers of the mobile terminal between the
original cell and the neighboring cell when the distance between the
mobile terminal and the original cell and the distance between the mobile
terminal and the neighboring cell are larger than the distance thresholds
R1 and R2.

[0057] The threshold for the number of the neighboring cells configured is
determined according to the distribution density of base stations and the
number of the neighboring cell configured contained in the neighboring
cell configuration table of a cell. If the number of the neighboring cell
configured contained in the neighboring cell configuration table of a
cell is greater than the corresponding threshold, then a cell with a
number of configured neighboring cells that is larger than the number
threshold for configured neighboring cells, is taken as an original cell.
The original cell is taken as the center to draw concentric circles, each
of which has a radius in a multiple relationship with that of the
smallest concentric circle. In this way, in the following processing, the
neighboring cells of the original cell can be divided into different
loops spaced by a distance equal to the radius of the smallest concentric
circles. The radiuses of the concentric circles are determined according
to the density of the base stations, where base stations are densely
distributed, the radius of the concentric circle is small, and where base
stations are discretely distributed, the radius of the concentric circle
is large.

[0058] The loop location threshold for the farthest neighboring cell,
which is a limitation to the loop location of the farthest neighboring
cell, is determined according to the density of the base stations in
different cities or suburbs and should be properly increased if the
distance between base stations is far. It is indicated, if the threshold
is exceeded, that the farthest neighboring cell is extremely far away
from the original cell, and that the coverage of the original cell is
large.

[0059] The loop number threshold for the configured neighboring cells
within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located refers to the maximum rational
number of the neighboring cells configured between the original cell and
the farthest neighboring cell. It is indicated, if the loop number
threshold is exceeded, that the neighboring cells are irrationally and
densely distributed between the original cell and the farthest
neighboring cell, and that there is a possibility that the original cell
provides cross-cell coverage. The loop number threshold is determined
according to the density of base stations and the geographic environment,
and typically, 3-4 loops are preferred.

[0060] The distance thresholds R1 and R2 are determined according to the
density of the base stations in different urban areas, it is impossible
that the original cell provides cross-cell coverage when the distance
between the mobile terminal and the original cell is within R1. It is
indicated by the exceeding of the distance between the mobile terminal
and the original cell over R2 that the mobile terminal is far away from
the original cell and the original cell meets a distance condition for a
cross-cell coverage determination. FIG. 3 visually shows the relationship
between the distances of a mobile terminal to the original cell and to
the neighboring cell and cross-cell coverage. When a mobile terminal is
handed over between an original cell and a neighboring cell, if the
distance between the mobile terminal and the original cell and the
distance between the mobile terminal and the neighboring cell are both
within R1, then neither the original cell nor the neighboring cell
provides cross-cell coverage; if the distance between the mobile terminal
and the original cell or the neighboring cell is larger than R1 but small
than R2, then it cannot be determined whether or not the original cell or
the neighboring cell provides cross-cell coverage; if the distance
between the mobile terminal and the original cell and the distance
between the mobile terminal and the neighboring cell are both greater
than R2, then both the original cell and the neighboring cell meet the
distance condition for a cross-cell coverage determination.

[0061] The number threshold for handovers of the mobile terminal between
the original cell and the neighboring cell refers to the times the mobile
terminal is handed over between the original cell and the neighboring
cell when the distance between the mobile terminal and the original cell
is greater than R2 and the distance between the mobile terminal and the
neighboring cell is smaller than R1 or greater than R1 but smaller than
R2. It is indicated, if the number threshold is exceeded, that occasional
factors such as a signal drifting of the original cell and a signal
reflection by other buildings cannot be the reason for the mobile
terminal' acquisition of a signal from the original cell and handover to
the original cell. The number threshold is input according to demands of
users, the larger the threshold is, the less the obtained cells having
cross-cell coverage are, and likewise, the larger the cross-cell coverage
of the cells is, the smaller the threshold is, and the less the obtained
cells having cross-cell coverage are.

[0062] Step 202: the comparison and determination unit determines whether
or not the number of the neighboring cells is greater than the threshold
for the number of the neighboring cells configured according to the
neighboring cell configuration table of a cell in the base station,
determines the cell does not have cross-cell coverage when the number of
neighboring cells configured contained in the neighboring cell
configuration table is smaller than the threshold, and then Step 212 is
executed, otherwise, Step 203 is executed by taking the cell as the
original cell.

[0063] Step 203: the processing unit calculates the distance between a
neighboring cell and the original cell according to the location
information table of the base station. The location information table of
the base station includes location information of the cells in all the
base stations in the whole network, wherein the location information
includes the azimuth and the longitude and latitude of a base station.
Therefore, the distance between the neighboring cell and the original
cell can be calculated according to a spherical distance calculation
formula based on longitudes and latitudes of the neighboring cell and the
original cell. The included angle between the neighboring cell and the
mainlobe of the original cell is calculated according to the calculated
distance in combination with the mainlobe of the original cell acquired
by the background of the base station and the neighboring cell
configuration table of the original cell.

[0064] the process of calculating the included angle between the
neighboring cell and the mainlobe of the original cell is as follows:
equally dividing the mainlobe of the original cell by an azimuth line,
and making a connecting line connecting the original cell and the
neighboring cell; the included angle formed between the connecting line
and the azimuth line represents the included angle between a neighboring
cell and the mainlobe of the original cell, the included angle should be
formed in half of the mainlobe of the original cell, and the neighboring
cell with an included angle smaller than half of the mainlobe is located
in the mainlobe of the original cell.

[0065] Step 204: the processing unit determines the loop location where
the neighboring cell locates by rounding up the ratio of the distance
between the neighboring cell and the original cell to the radius of the
smallest concentric circle, for instance, the neighboring cell is located
in the third loop if the ratio is 3, and is located in the fourth loop if
the ratio is 3.2. The loop location of the neighboring cell farthest from
the original cell, that is, the greatest loop location, is determined by
sorting the neighboring cells according to the descending order of the
loop locations, and then the loop location of the farthest neighboring
cell is output to the comparison and determination unit.

[0066] Step 205: the compassion and determination unit compares the loop
location where the farthest neighboring cell is located output by the
processing unit with the loop location threshold for the farthest
neighboring cell input by the input unit, when the former is greater than
the latter, Step 206 is executed, otherwise, determines the original cell
has no cross-cell coverage, and then Step 212 is executed.

[0067] Step 206: the processing unit makes a statistics of the number of
loops where neighboring cells within the mainlobe of the original cell in
each loop are located, excluding softer handover cells, according to a
loop location of neighboring cell and an included angle between the
neighboring cell and the mainlobe of the original cell. The softer
handover cells refer to that: handover occurs between cells in one base
station. Since the softer handover cells have the same longitude and
latitude, and the distance between them is 0, the softer handover cells
are not taken into consideration during the statistics. The statistics
process is as follows: the processing unit determines which neighboring
cell is located in the mainlobe of the original cell according to the
included angle between the neighboring cell and the mainlobe of the
original cell, determines the number of the loops where neighboring cells
are located according to the loop locations of the neighboring cells,
thereby acquiring the number of the loops where neighboring cells within
the mainlobe of the original cell in each loop are located, further
acquiring the number of the loops, on which configured neighboring cells
within the mainlobe of the original cell in the loop, on which the
farthest neighboring cell is located, are located, which is output to the
comparison and determination unit.

[0068] Step 207: the comparison and determination unit compares the number
of the loops, on which configured neighboring cells within the mainlobe
of the original cell in the loop, on which the farthest neighboring cell
is located, are located, which is output by the processing unit, with the
loop number threshold for the configured neighboring cells within the
mainlobe of the original cell in the loop on which the farthest
neighboring cell is located, which is input by the input unit. Step 208
is executed when the former is greater than the latter, otherwise,
determines the original cell has no cross-cell coverage, and Step 212 is
executed.

[0069] Step 208: the processing unit acquires, by inquiring the specific
information recorded by the background of the base station on the
communication of the mobile terminal and looking up the neighboring cell
configuration table of the original cell, a record on the handovers of
the mobile terminal between the original cell and a neighboring cell, the
distance between the mobile terminal and the original cell and the
distance between the mobile terminal and a neighboring cell during each
handover, and the times of handovers of the mobile terminal between the
original cell and the neighboring cell, and outputs the acquired
information to the comparison and determination unit. The specific
information recorded by the background of the base station on the
communication of the mobile terminal includes: a record on the handovers
of the mobile terminal between cells, and the distance between the mobile
terminal and each cell during each handover.

[0070] Step 209: the comparison and determination unit compares the
distance between the mobile terminal and the original cell and the
distance between the mobile terminal and a neighboring cell, output by
the processing unit, with distance thresholds R1 and R2 input by the
input unit, Step 210 is executed when the distance between the mobile
terminal and the original cell output by the processing unit is greater
than the distance threshold R2 input by the input unit and the distance
between the mobile terminal and the neighboring cell output by the
processing unit is smaller than R1, or greater than R1 but smaller than
R2, otherwise, determines the original cell has no cross-cell coverage,
and then Step 212 is executed.

[0071] Step 210: the comparison and determination unit compares the number
of handovers of the mobile terminal between the original cell and a
neighboring cell output by the processing unit with the number threshold
for handovers of the mobile terminal between the original cell and the
neighboring cell input by the input unit, executes Step 211 when the
former exceeds the latter, otherwise, determines the original cell has no
cross-cell coverage, and then executes Step 212.

[0072] Step 211: the comparison and determination unit determines the
original cell provides cross-cell coverage and outputs the result of the
determination to the output unit, the output unit outputs the result of
the determination, and the background of the base station regulates the
configuration parameters of the original cell to limit the coverage of
the original cell in a proper one.

[0073] Step 212: the next cell is processed.

[0074] By modifying part of the condition, the present disclosure can make
another determination on whether or not the original cell suffers from
cross-cell coverage, that is, whether or not the original cell is crossed
by a neighboring cell. Referring to FIG. 2, after Step 208, the
comparison and determination unit compares the distance between the
mobile terminal and the original cell and the distance between the mobile
terminal and a neighboring cell, input by the processing unit, with the
distance thresholds input by the input unit; determines the number for
handovers of the mobile terminal between the original cell and the
neighboring cell when the distance between the mobile terminal and the
neighboring cell is greater than R2 and the distance between the mobile
terminal and the original cell is smaller than R1, or greater than R1 but
smaller than R2; and determines the original cell suffers from cross-cell
coverage when the number for handovers of the mobile terminal between the
original cell and the neighboring cell input by the processing unit is
greater than the number threshold input by the input unit. Subsequently,
the background of the base station regulates the configuration parameters
of the original cell to limit the coverage thereof in a proper one.

[0075] After Step 208, a determination on whether or not the original cell
provides cross-cell coverage and a determination on whether or not the
original cell suffers from cross-cell coverage can be carried out
synchronously or independently.

[0076] The condition for determining the cross-cell coverage of the
original cell is described below in detail by reference to a specific
example, as shown in FIG. 4.

[0077] The original cell is X, neighboring cells are A1-A5 which are
respectively located in the second to the sixth loop, and the farthest
neighboring cell is A5. According to the input of the input unit, the
loop location threshold for the farthest neighboring cell is 4, the loop
number threshold for the configured neighboring cells within the mainlobe
of the original cell in the loop on which the farthest neighboring cell
is located is 3, the number threshold for handovers of the mobile
terminal between the original cell and the neighboring cells is 5, and R2
is 2000 m, wherein the distance between two loops is 500 m. It can be
seen from FIG. 4 that:

[0078] (1) the farthest neighboring cell A5 is in the sixth loop, thus the
condition for a cross-cell coverage determination is met;

[0079] (2) the cell X has 4 loops in which neighboring cells are
configured before the neighboring cell A5, thus the condition for a
cross-cell coverage determination is met; and

[0080] (3) the distance between the mobile terminal and the original cell
X is longer than 2500 m (greater than R2), and if the processing unit
detects, from the background of the base station, that the number of
handovers of the mobile terminal between the original cell and the
neighboring cells is 10,

[0081] then it can be determined that the original cell provides
cross-cell coverage.

[0082] Based on the aforementioned method, the present disclosure further
provides an apparatus for estimating cross-cell coverage, which at least
comprises, as shown in FIG. 5, a processing unit 502 and a comparison and
determination unit 503.

[0083] The comparison and determination unit 503 is configured to: find,
according to the neighboring cell configuration table of a cell in a base
station, a cell with the number of configured neighboring cells is
greater than a number threshold for configured neighboring cells; take
the found cell as an original cell; and determine the original cell
provides cross-cell coverage or suffers cross-cell coverage when a
cross-cell coverage evaluation parameter of the original cell exceeds a
cross-cell coverage evaluation threshold, and the processing unit 502 is
configured to carry out a processing to obtain the cross-cell estimation
parameter of the original cell.

[0084] Specifically, the processing unit 502 is configured to process the
following information to get the cross-cell coverage evaluation parameter
of the original cell: detailed information during a call process of a
mobile terminal, the mainlobe of the original cell, and the location
information table of the base station obtained from the background of the
base station, and the information in the neighboring cell configuration
table of the original cell. The processing unit 502 is also configured to
send the cross-cell coverage estimation parameter to the comparison and
determination unit 503. The cross-cell coverage estimation parameter of
the original cell including: a loop on which a farthest neighboring cell
is located; the number of loops, on which configured neighboring cells
within the mainlobe of the original cell in the loop, on which the
farthest neighboring cell is located, are located; the distance between
the mobile terminal and the original cell and the distance between the
mobile terminal and a neighboring cell; and the times of handover of the
mobile terminal between the original cell and the neighboring cell. The
specific processing carried out by the processing unit 502 can be
understood by reference to the description given in FIG. 2 and is
therefore not illustrated here repeatedly.

[0085] Specifically, the comparison and determination unit 503 is
configured to compare the cross-cell coverage estimation parameter sent
by the processing unit 502 with the cross-cell coverage estimation
parameter threshold input by the input unit 501, determines the original
cell provides cross-cell coverage when the cross-cell coverage estimation
parameter is greater than the cross-cell coverage estimation parameter
threshold, or determines the original cell provides no cross-cell
coverage when the cross-cell coverage estimation parameter is not greater
than the cross-cell coverage estimation parameter threshold.

[0087] determine whether a loop on which a farthest neighboring cell is
located is larger than a loop location threshold for the farthest
neighboring cell;

[0088] when determining that the loop on which the farthest neighboring
cell is located is larger than the loop location threshold for the
farthest neighboring cell, determine whether a number of loops, on which
configured neighboring cells within the mainlobe of the original cell in
the loop, on which the farthest neighboring cell is located, are located,
is larger than a loop number threshold for the configured neighboring
cells within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located;

[0089] when determining the number of loops, on which configured
neighboring cells within the mainlobe of the original cell in the loop,
on which the farthest neighboring cell is located, are located, is larger
than the loop number threshold for the configured neighboring cells
within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located, compare distances of the mobile
terminal to the original cell and to a neighboring cell with a first
distance threshold and a second distance threshold;

[0090] when the distance of the mobile terminal to the original cell is
larger than the second distance threshold, and the distance of the mobile
terminal to the neighboring cell is either smaller than the first
distance threshold, or larger than the first distance threshold and
smaller than the second distance threshold, determine whether the number
of handovers of the mobile terminal between the original cell and the
neighboring cell exceeds a number threshold for handovers of the mobile
terminal between the original cell and the neighboring cell; and

[0091] when determining that the number of handovers of the mobile
terminal between the original cell and the neighboring cell exceeds the
number threshold for handovers of the mobile terminal between the
original cell and the neighboring cell, determine that the original cell
provides cross-cell coverage. The first distance threshold is the maximum
distance value for determining a cell provides definitely no cross-cell
coverage, and the second distance threshold is the minimum distance value
for determining a cell provides definitely cross-cell coverage.

[0092] The comparison and determination unit, when determining the number
of loops, on which configured neighboring cells within the mainlobe of
the original cell in the loop, on which the farthest neighboring cell is
located, are located, is larger than the loop number threshold for the
configured neighboring cells within the mainlobe of the original cell in
the loop on which the farthest neighboring cell is located, is further
configured to:

[0093] compare distances of the mobile terminal to the original cell and
to the neighboring cell with the first distance threshold and the second
distance threshold;

[0094] when the distance of the mobile terminal to the neighboring cell is
larger than the second distance threshold, and the distance of the mobile
terminal to the original cell is either smaller than the first distance
threshold, or larger than the first distance threshold and smaller than
the second distance threshold, determine whether the number of handovers
of the mobile terminal between the original cell and the neighboring cell
exceeds the number threshold for handovers of the mobile terminal between
the original cell and the neighboring cell; and

[0095] when determining that the number of handovers of the mobile
terminal between the original cell and the neighboring cell exceeds the
number threshold for handovers of the mobile terminal between the
original cell and the neighboring cell, determine that the original cell
suffers from cross-cell coverage.

[0096] The comparison and determination unit 503 is configured to:

[0097] determine whether a loop on which a farthest neighboring cell is
located is larger than a loop location threshold for the farthest
neighboring cell;

[0098] when determining that the loop on which the farthest neighboring
cell is located is larger than the loop location threshold for the
farthest neighboring cell, determine whether a number of loops, on which
configured neighboring cells within the mainlobe of the original cell in
the loop, on which the farthest neighboring cell is located, are located,
is larger than a loop number threshold for the configured neighboring
cells within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located;

[0099] when determining the number of loops, on which configured
neighboring cells within the mainlobe of the original cell in the loop,
on which the farthest neighboring cell is located, are located, is larger
than the loop number threshold for the configured neighboring cells
within the mainlobe of the original cell in the loop on which the
farthest neighboring cell is located, compare distances of the mobile
terminal to the original cell and to a neighboring cell with a first
distance threshold and a second distance threshold;

[0100] when the distance of the mobile terminal to the neighboring cell is
larger than the second distance threshold, and the distance of the mobile
terminal to the original cell is either smaller than the first distance
threshold, or larger than the first distance threshold and smaller than
the second distance threshold, determine whether a number of handovers of
the mobile terminal between the original cell and the neighboring cell
exceeds a number threshold for handovers of the mobile terminal between
the original cell and the neighboring cell; and

[0101] when determining that the number of handovers of the mobile
terminal between the original cell and the neighboring cell exceeds the
number threshold for handovers of the mobile terminal between the
original cell and the neighboring cell, determine that the original cell
suffers from cross-cell coverage.

[0102] The apparatus further comprises an input unit 501 and an output
unit 504.

[0103] The input unit 501 is configured to send a threshold for the number
of the neighboring cells configured and the cross-cell coverage
estimation threshold to the comparison and determination unit 503,
wherein the cross-cell coverage evaluation threshold includes: the loop
location threshold for the farthest neighboring cell, the loop number
threshold for the configured neighboring cells within the mainlobe of the
original cell in the loop on which the farthest neighboring cell is
located, the distance thresholds of the mobile terminal to the original
cell and to the neighboring cell, and the number threshold for handovers
of the mobile terminal between the original cell and the neighboring cell
when the distances of the mobile terminal to the original cell and to the
neighboring cell are larger than the distance thresholds.

[0104] The output unit 504 is configured to output the result of the
determination carried out by the comparison and determination unit 503.

[0105] The mentioned above is only preferred embodiments of the present
disclosure but not limitation for the protection scope of the present
disclosure, various modification and variations can be devised by those
skilled in this art, and it should be understood that any modification,
equivalent and improvement devised without departing from the scope of
the present disclosure belong to the protection scope of the present
disclosure.